Polymerization of monomeric materials to produce thermoplastic polymers is carried out in a variety of ways, including solution polymerization, suspension polymerization and emulsion polymerization. As a result, recovery of the polymer involves drying and/or devolatization in order to produce an intermediate product which can thereafter be formed into a final product. At the present time such drying and devolatilization is carried out by steam stripping, heating and flashing, film evaporization, extrusion devolatilization, etc. All of these methods have the common problem of being highly energy intensive and requiring expensive equipment which requires the maintenance of critical conditions and high cost of maintenance. For example, the cost of steam in steam stripping and preheating and flashing in film evaporators is quite high. However, electrical heating, such as is generally used in extrusion devolatilization, is even higher. In addition, the energy utilized to supply heat is substantially completely lost during the process, as by discharging the same to the atmosphere. Further, such polymers are often produced in powdered form (fluff) which is difficult and expensive to handle and ship to an end use location. Consequently, the polymer is generally agglomerated and pelleted for ease and economy of handling and transportation. At the present time such agglomeration and pelleting involves continuous intensive mixing, then extrusion through dies and finally cutting into pellets. During this operation, the fluff is melted for agglomeration at temperatures typically between about 100.degree. and 450.degree. F., usually the latter. Thus, the process is highly energy intensive and the input energy is usually vented to the atmosphere, thus resulting in substantial losses of energy. In addition, such processing equipment is expensive, difficult to operate and difficult to maintain. Further, intensive mixing and extrusion, if not properly controlled, often results in damaging the final polymer.